Running really rough, no power, backfiring.

[1orange2]

I'm having an odd problem. My car just started running really rough, backfiring and basically sounding like a tractor running on 3 cylinders, shaking etc.

It has electronic ignition, weber 38/38.

I just installed new ngk bp6es plugs also. cap and rotor are new. I'm going to try another set of wires and see if that helps at all.

It did have a small leak at the base of the carb and intake manifold, so I replaced the studs and gasket. I've checked the vacuum caps on intake runners 1 and 4. I also noticed that my dipstick isn't sealed per say, but if i plug it with my thumb no change.

Any thoughts?

[1orange2]

[TobyB]

Given that you have Botch plug wires, that'd be the first thing I'd check, too.

The wire tends to pull out of the spark plug ends. You can screw them back

down tighter, and they then work again... for a while.

Then go through all the parts you replaced, things like, did the carbon wiper

in the cap fall out, a plug wire push its way out of the distributor cap (air can

get trapped, then it expands when hot) maybe the rotor's not seated all

the way, or it's loose, or bad... et cetera...

It's also worth testing the plugs. I've never had a bad NGK, but that doesn't

mean yours are all good.

just some thoughts...

t

[1orange2]

Just did a compression check.

Cyl 1- 125

Cyl 2- 127

Cyl 3- 0

Cyl 4- 0

Not burning blue smoke, hasn't overheated...

[Chamonix72]

Blown head gasket?

Just did a compression check.

Cyl 1- 125

Cyl 2- 127

Cyl 3- 0

Cyl 4- 0

Not burning blue smoke, hasn't overheated...

[dbmw2002]

Sounds so familar, just did my head gasket and your description of the shakin was a dead ringer for mine, probably the gap between 3-4 blew, thus no water or oil leakage just wont run right and shakes her head like a wild mare. AutohauzAZ was my choice of vendors for a full top end gasket set, I think it ran a half a benjamin, watch out for project creep but do it right when you are in there, she will scream again!

[1orange2]

anybody have a cheap m10?...lol sigh

[Chamonix72]

As long as you didn't warp the head, and if you say it didn't overheat, it may not be, then changing a head gasket isn't the end of the world. It's a hell of a lot easier than replacing a motor.

[c.d.iesel]

a compression check.

Cyl 1- 125

Cyl 2- 127

Cyl 3- 0

Cyl 4- 0

so it's obvious that the head has been off just yesterday,

i'd say it's some bonehead mistake - simple to 'adjust'-

by removing the head and showing us what the head

gasket and head looks like

[jgerock]

Yikes. Wonder if the head bolt cavities were cleaned out before the head was bolted back down.

[1orange2]

Yeah, i'm going to take it apart now and see. Otherwise I have a fully rebuilt m42 just sitting in the garage, although I prefer the m10 hands down.

[nbristow01]

Yikes. Wonder if the head bolt cavities were cleaned out before the head was bolted back down.

That was my first thought

[1orange2]

While i'm debating all of this.....

My roomate has a 1992 e36 318i 5spd with 143,xxx. We coincidentally just rebuilt the entire thing top to bottom, new clutch etc.

I've been doing some searching, but here are a few ?'s.

The m10 and m30 use a different shape than the m4x/m50/s50

I can use the bellhousing from his trans on the 5spd already in my car?

I'd want a 318is fuel pump?

Any other options?

[Mike Self]

carefully examine the head surface where the gasket blew to make sure there was no track burned in the aluminum head. That happened to my engine--blown gasket between #3 & 4 cyls--and it etched a groove in the head surface. Our local performance machine shop welded up the groove and gently surfaced the head (minimal metal removal) to make it flat where the weld was. Stuck it back on and all was good.

As for the M42 motor...no it won't fit the M10 tranny's bellhousing. You'll have to use the appropriate tranny and rig up an electronic speedometer, as the M42 tranny doesn't have a provision for a mechanical speedo.

cheers

mike

[1orange2]

Few more questions here...

Will the e36 radiator work?

e36 5 spd Driveshaft will bolt to the diff?

anything i'm missing?